Sains Malaysiana 43(2)(2014): 219–225
Possibility of Improving the Properties of Mahang Wood (Macaranga sp.)
through Phenolic Compreg Technique
(Kemungkinan untuk Meningkatkan Sifat Kayu Mahang (Macaranga sp.)
melalui Teknik
Compreg Fenolik)
A.F. ANG1, A.
ZAIDON*1, E.S.
BAKAR1, S.
MOHD
HAMAMI1, U.M.K.
ANWAR2
&
M.
JAWAID3
1Faculty of Forestry, Universiti Putra Malaysia, 43400 Serdang,
Selangor D.E. Malaysia
2Forest Research Institute Malaysia, 52109 Kepong, Selangor
D.E. Malaysia
3Institute of Tropical Forestry and Forest Products, Universiti
Putra Malaysia
43400 Serdang, Selangor D.E. Malaysia
Diserahkan: 2 Januari 2013/Diterima: 17 Mei 2013
ABSTRACT
Lesser known wood species (LKS) have the potentials to
become alternative sources of timber supply for wood based industries if their
properties can be improved. In this study, Mahang wood (Macaranga sp.) was impregnated 15% (w/v) low
molecular weight phenol formaldehyde (LMWPF) followed by compressing
in a hot press at 70, 60 and 50% compression ratios (CR).
The treated wood was partially dried in an oven at 65°C until 10%
moisture content and subsequently followed by curing at 150°C for 30 min
in a hot press. The results showed that the phenolic compreg technique
had successfully increased the dimensional stability and mechanical properties
of the wood. The polymer retention calculated based on weight gain regardless
of compression ratio was approximately 30%. The majority of the properties were
improved by the degree of compression in a hot press. Nevertheless, thickness
swelling and swelling coefficient increased which were due to spring back
effect. As regards to specific strength (strength to density ratio), the compreg wood displayed lower strength and stiffness in lateral direction compared
with untreated solid wood. However, the specific compressive strength
perpendicular to grain and hardness of the compreg wood were superior
than untreated solid wood. The treatment had also changed the wood into highly
resistant to fungal decay.
Keywords: Compression ratio; Mahang wood; phenol formaldehyde; Pycnoporus sanguineus; swelling coefficient
ABSTRAK
Spesies kayu kurang dikenali (LKS)
mempunyai potensi untuk dijadikan sebagai bekalan kayu alternatif kepada
industri kayu jika sifat mereka yang kurang baik dapat dipertingkatkan. Dalam
kajian ini, compreg Mahang diperbuat
dengan pengisitepuan resin fenol formaldehid berat molekul rendah (LMWPF)
(15% w/v) diikuti dengan mampatan di bawah haba pada kadar mampatan 70, 60 dan
50%. Kayu yang telah diisitepuan dengan resin dikering sebahagian pada suhu
65°C sehingga mencapai kelembapan 10% kemudian diikuti dengan kering sepenuhnya
pada suhu 150°C selama 30 min di bawah penekan haba. Keputusan menunjukkan
bahawa teknik compreg fenolik telah berjaya meningkatkan kestabilan
dimensi dan sifat mekanikal kayu. Retensi polimer dikira berdasarkan peratus
berat dapatan tanpa mengambil kira kadar mampatan adalah lebih kurang 30%.
Majoriti sifat-sifat kayu telah ditingkatkan oleh darjah mampatan di dalam
penekan haba. Walau bagaimanapun, peningkatan dalam pembengkakan tebal dan
pekali pembengkakan adalah disebabkan oleh kesan pemantulan semula. Berkenaan
kekuatan khusus (nisbah kekuatan kepada ketumpatan), kayu compreg menunjukkan
kekuatan dan kekakuan yang lebih rendah dalam arah sisi berbanding kayu yang
tidak dirawat. Walau bagaimanapun, kekuatan khusus bagi mampatan serenjang urat
kayu dan kekerasan kayu compreg adalah lebih baik daripada kayu yang
tidak dirawat. Rawatan ini juga telah mengubah kayu menjadi sangat tahan kepada
kerosakan kulat.
Kata kunci: Fenol formaldehid; kadar mampatan;
kayu Mahang; pekali pembengkakan; Pycnoporus sanguineus
RUJUKAN
Abdul Samad, A.R., Mohd Ashhari, Z. & Othman, M.S. 2009.
Sustainable forest management practices and West Malaysian log market. Asian
Social Science 5(6): 69-76.
Ashaari, Z., Barnes, H.M., Lyon, D.E., Vasishth, R.C. &
Nicholas, D.D. 1990a. Effect of aqueous polymer treatments on wood properties.
Part I: Treatability and dimension stability. IRG/ WP/3610.
Ashaari, Z., Barnes, H.M., Lyon, D.E., Vasishth, R.C. &
Nicholas, D.D. 1990b. Effect of aqueous polymer treatments on wood properties.
Part II: Mechanical properties. IRG/WP/3611.
ASTM. 1972. American society for testing materials:
Accelerated laboratory test of natural decay resistance of woods. ASTM
D2017-71. Philadelphia, USA.
BSI. 1957. British standard 373:1957. Methods of testing
small clear specimens of timber. British Standard Institution.
Furuno, T., Imamura, Y. & Kajita, H. 2004. The
modification of wood by treatment with low molecular weight phenol-formaldehyde
resin: A properties enhancement with neutralized phenolic-resin and resin
penetration into wood cell walls. Wood Science and Technology 37:
349-361.
Islam, M.S., Hamdan, S., Talib, Z.A., Ahmed, A.S. &
Rahman, M.R. 2012. Tropical wood polymer nanocomposite (WPNC): The impact of
nanoclay on dynamic mechanical thermal properties. Composite Science and
Technology 72: 1995- 2001.
Kultikova, E.V. 1999. Structure and properties relationships
of densified wood. Thesis Virgina: Virginia Tech, Blacksburg (unpublished).
Norimoto, M. & Gril, J. 1993. Structure and properties
of chemically treated woods. In Recent Research on Wood and Wood-based
Materials, edited by Shiraishi, N., Kajita, H. & Norimoto, M. Barking:
Elsevier.
Rabiatol Adawiah, M.A., Zaidon, A., Nur Izreen, F.A., Bakar,
E.S., Mohd Hamami, S. & Paridah, M.T. 2012. Addition of urea as formaldehyde
scavenger for low molecular weight phenol formaldehyde-treated compreg wood. Journal of Tropical Forest Science 24(3): 348-357.
Rowell, R.M. & Konkol, P. 1987. Treatments that enhance
physical properties of wood. Gen. Tech. Rep. FPL-GTR-55. Madison, U.S.
Department of Agriculture, Forest Service, Forest Product Laboratory.
Rowell, R.M. & Youngs, R.L. 1981. Dimensional
stabilization of wood in use. U.S. For. Serv., For. Prod. Res. Note FPL -0243.
Forest Product Laboratory, Wisconsin.
Shams, M.I., Kagemori, N. & Yano, H. 2006. Compressive
deformation of wood impregnated with low molecular weight phenol formaldehyde
(PF) resin IV. Species dependency. Journal of Wood Science 52: 189-193.
Shams, M.I., Yano, H. & Endou, K. 2004. Compressive
deformation of wood impregnated with low molecular weight phenol formaldehyde
(PF) resin I: Effects of pressing pressure and pressure holding. J. Wood
Sci. 50: 337-342.
Welzbacher, C.R., Rapp, A.O., Haller, P. & Wehsener, J.
2005. Biological and mechanical properties of densified and thermally modified
spruce. In Wood Modification. 2nd European Conference on Wood Modification, edited
by BFH - Institute of Wood Chemistry and Chemical Technology of Wood, editor.
2005 October 06-07; Gottingen.
Yeom, F.B.C. 1984. Lesser-known tropical wood species: How
bright is their future? Unasylva 36: 3-16.
Zaidon, A. 2009. Improvement of raw materials from
underutilised timber species through chemical and densification treatments for
value added laminated products. End of project report submitted to the Ministry
of Science and Technology, Malaysia.
Zaidon, A., Bakar, E.S. & Paridah, M.T. 2010. Compreg
laminates from low density tropical hardwoods. Proceedings of the
International Convention of Society of Wood Science and Technology and United
Nations Economic Commission for Europe Timber Committee. 11–14
October 2010, Geneva.
*Pengarang
untuk surat-menyurat; email: zaidon@putra.upm.edu.my
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